Re:Ask HN: Even if time travel was possible, wouldn't it sti...
by simonblack on Monday November 08, 2021 @03:39PM
(#29153926)
it seems to me the observable universe can be sliced into a 3d grid
Unfortunately when time is taken into consideration, we're looking at a 4D (at least, but let's be minimalist) space-time.
It seems generally accepted that we are living in a multiverse, so that even if time-travel was possible, even the act of breathing would enforce a move to a different universe from the universe where you had started your time-travel, and which you could never return to.
So, you can go back and kill Hitler (or even your own grandmother). But you can never go back and say "See what I did!".
Unfortunately when time is taken into consideration, we're looking at a 4D (at least, but let's be minimalist) space-time.
It seems generally accepted that we are living in a multiverse, so that even if time-travel was possible, even the act of breathing would enforce a move to a different universe from the universe where you had started your time-travel, and which you could never return to.
So, you can go back and kill Hitler (or even your own grandmother). But you can never go back and say "See what I did!".